Bio 1010c Exam 4

When an aminoacyl-tRNA synthetase charges a tRNA it results in the release of which molecule? mRNA ATP AMP pyrophosphate AMP and pyrophosphate

AMP and pyrophosphate

Define cancer AND state the GENERAL cause of all types of cancer.

Cancer is unrestrained cell growth. All cancer is caused by DNA mutation.

Chin dimples is recessive (c) to having no chin dimples which is dominant (C). Also, normal pigmentation is dominant (A) to albinism (a) in humans. A woman who is heterozygous for both traits marries a man heterozygous for albinism and who has chin dimples. What are the genotypes and ratios of genotypes for their offspring?

CcAA: 1/8, CcAa: 1/4, ccAA: 1/8, ccAa: 1/4, Ccaa: 1/8, ccaa: 1/8

Two babies are mixed up in the hospital nursery. The blood types of Couple 1 are A and O and the blood types of Couple 2 are AB and B. Baby Joe has blood type O and Baby Jane has blood type B. Who are the parents of Baby Joe and Baby Jane? Couple 1, Baby Joe; Couple 2, Baby Jane Couple 1, Baby Jane; Couple 2, Baby Joe Couple 1, Baby Joe; Couple 2 could not be the parents of either baby Couple 2, Baby Joe; Couple 1 could not be the parents of either baby From these combinations of blood types, it is impossible to determine

Couple 1, Baby Joe; Couple 2, Baby Jane

Explain what the central dogma of molecular biology means in your own words.

DNA is the template that codes for all polypeptides. Before polypeptides can be made, the DNA must be transcribed into a mRNA first. That mRNA can leave the nucleus and be translated in the cytoplasm by the ribosome to make the polypeptide.

Homologous chromosomes are identical copies of each other. True False

False

Principle(s) of the chromosome theory of inheritance include: Check all that apply. Genes are transmitted from parent to offspring via chromosomes. Gametes contain either a maternal or paternal set of chromosomes. Diploid cells contain a maternal and paternal set of chromosomes. The paternal and maternal chromosomes segregate independently during meiosis. Gametes are haploid.

Genes are transmitted from parent to offspring via chromosomes. Diploid cells contain a maternal and paternal set of chromosomes. The paternal and maternal chromosomes segregate independently during meiosis. Gametes are haploid.

n a test cross, peas of an unknown genotype are crossed with peas of a known genotype. In this example, smooth peas are the unknown and wrinkled peas are the known (rr). If half of the offspring from that cross are smooth and half are wrinkled, what is the genotype of the unknown plant? Incomplete dominance Homozygous dominant: RR Homozygous recessive: rr Heterozygous: Rr

Heterozygous: Rr

Originally, genetic inheritance was thought to be a function of the blending of traits from the two parents. Which exception to Mendel's rules is an example of blending? X linkage Polygenic inheritance Incomplete dominance Codominance Pleiotropism

Incomplete dominance

If a cell's splicesomes were mutated so they no longer functioned normally, what consequences would result? Introns would remain in the mature mRNA. Exons would be missing in the mature mRNA. Transcription would cease. A functional protein would still be produced. RNA processing would remain intact.

Introns would remain in the mature mRNA.

Eyelash length is an inherited trait. In the human population, there is an eyelash length gene. There are two possible variants of this gene - an allele for long eyelashes (> 1cm) and an allele for short eyelashes (1 cm or less). The allele for long eyelashes is dominant (L) and the allele for short eyelashes is recessive (l). An individual who is heterozygous for eyelash length would have which of the following phenotypes?

Long eyelashes

Which of the following statements about cancer is FALSE? It is characterized by uncontrolled cell division. Over 1 million Americans are diagnosed with cancer each year. Most cancers involve genetic changes that are passed from parent to offspring. At least 80% of all human cancers are related to exposure to carcinogens. It is caused by an accumulation of mutations.

Most cancers involve genetic changes that are passed from parent to offspring.

Which of the following statements is FALSE concerning sister chromatids? The formation of sister chromatids doubles the amount of DNA in a cell. Sister chromatids consist of two identical copies of a single homologue. Sister chromatids are held together at the centromere by kinetochore proteins. Sister chromatids are formed during the S phase of the cell cycle. Sister chromatids separate during telophase.

Sister chromatids separate during telophase.

Colchicine is a toxin that binds to tubulin proteins and prevents microtubules from polymerizing. What affect might this have on dividing cells? Cells will be able to complete mitosis, but cytokinesis will not occur Chromosomes will not be able to condense, so mitosis will not occur Sister chromatids will not be properly separated into separate daughter cells Replicated chromosomes will not be able to stick together, so sister chromatids will not properly sort into daughter nuclei The cell will not be able to move past the restriction point, so DNA will not be replicated.

Sister chromatids will not be properly separated into separate daughter cells

A mutation occurs in a gene that encodes a G1-cyclin, such that the protein is unable to bind to its CDK. How will this affect the cell cycle? The cell will be stuck in G1 and will not advance through the cell cycle. The cell will replicate its DNA, but will be unable to progress through mitosis. The cell will rapidly replicate its DNA and progress through mitosis, causing uncontrolled cell division, and leading to cancer. The cell will proceed thru mitosis without replicating its DNA. The cell will proceed to the S phase, and DNA repair enzymes will repair the mutated cyclin when it replicates the DNA.

The cell will be stuck in G1 and will not advance through the cell cycle.

If a DNA template strand has a sequence of 3′ TACAATGTAGCC 5′, then the RNA produced from it will be which sequence? 3′TACAATGTAGCC5′ 5′ATGTTACATCGG3′ 5′AUGUUACAUCGG3' 3′AUGUUACAUCGG5′ 3′ATGTTACATCGG5′

5′AUGUUACAUCGG3'

The process by which haploid cells are produced from diploid cells is called sexual reproduction. mitosis. fertilization. meiosis. reduction.

meiosis.

What factors are recognized by the cell in order to recognize the stop codon and disassemble the translation machinery? elongation factors release factors transcription factors initiation factors mRNA factors

release factors

Which of the following serves as the "translator" or intermediary between an mRNA codon and an amino acid? rRNA snRNA tRNA siRNA snRNPs

tRNA

What phase of meiosis would you be watching if the chromosomes appear to be gathered together into nuclei? metaphase II telophase I mid-prophase I prophase II anaphase I

telophase I

Most oncogenes encode proteins that function in cell growth signaling pathways. True False

true

RNA polymerase II of eukaryotes always requires more than one general transcription factor to initiate transcription. True False

true

What is the function of the poly A tail? The poly A tail is required for the termination of translation, it is recognized by the release factor proteins The poly A tail is required for the mRNA to resume its double helical structure The poly A tail increases mRNA stability in eukaryotes. The poly A tail decreases mRNA stability in eukaryotes. The poly A tail serves as a termination sequence for RNA polymerase III.

The poly A tail increases mRNA stability in eukaryotes.

Human genetic disease/disorders can be caused by an autosomal recessive trait. translocations. a deletion in a chromosome. a mutant allele that is dominant tot he wild-type allele. all of the above.

all of the above.

The two-factor crosses performed by Mendel support the observation that alleles for a given trait are distributed randomly among an individual's gametes independent of the alleles for other traits. traits that are encoded by genes on different chromosomes are never found within the same gamete. the F1 generation can display phenotypes in combinations different from those seen in the P generation. the F2 generation will only display phenotypes in the same combinations as the P generation. self-fertilization of the F1 generation will produce 100% heterozygous plants at both loci.

alleles for a given trait are distributed randomly among an individual's gametes independent of the alleles for other traits.

Most human embryos that are aneuploid result in Down's syndrome. result in sterility. are spontaneously aborted in the first trimester. can develop and survive to adulthood. are usually the result of increased nondisjunction in the gametes of older men.

are spontaneously aborted in the first trimester.

Cyclin-dependent kinases (Cdk's) catalyze the phosphorylation of targeted proteins, phosphorylation is a process that decreases the mass of the protein. makes the targeted proteins hydrophobic. changes the shape and function of the targeted proteins. gives the proteins a three-dimensional shape. blocks the cell cycle from proceeding.

changes the shape and function of the targeted proteins.

Which of the following occurs during metaphase of mitosis? chromatin is visible. chromosomes are still decondensed. chromosomes line up in the middle of the cell. chromosomes undergo gene transcription. the "beads on a string" structure is visible.

chromosomes line up in the middle of the cell.

A haploid cell is a cell in which the genes are arranged haphazardly. containing only one copy of each chromosome. that has resulted from the process of mitosis. with twice the number of chromosomes of a diploid cell. None of the above

containing only one copy of each chromosome.

Because more than one codon can specify the same amino acid, the genetic code is said to be repetitive. redundant. reverse. degenerate. wobbly.

degenerate.

An organized unit of DNA sequences that enables a segment of DNA to be transcribed into RNA and ultimately results in the formation of a functional product is called a _______. chromosome trait allele gene expression

gene

Which of the following statements about the cell cycle is correct? The cell cycle is a sequence of replications and divisions that produces a new cells. The phases of the cell cycle are G1, S, and M phases. In actively dividing cells, the S and G2 phases are collectively known as interphase. When the S phase of the cell cycle is finished, a cell has twice as many chromatids as the number of chromosomes in the G1 phase. During G2 phase, the cell grows and copies its chromosomes in preparation for cell division.

When the S phase of the cell cycle is finished, a cell has twice as many chromatids as the number of chromosomes in the G1 phase.

Hemophilia is a recessive sex linked disorder in humans resulting in an inability to properly clot blood for individuals with the disease. A woman who is a carrier for hemophilia marries a man who does not have hemophilia. What gametes can the woman make?

Xh and XH

During crossing over, an incomplete exchange of genetic material occurs. This would most likely produce a deficiency in one homologue and a duplication in the other homologue. a deficiency in both homologues. a deficiency in one homologue and an inversion in the other homologue. a reciprocal translocation. a duplication in one homologue and an inversion in the other homologue.

a deficiency in one homologue and a duplication in the other homologue.

What features of meiosis allow for independent assortment of chromosomes? Random alignment of homologous sister chromatids on the metaphase plate Separation of sister chromatids Reduction of chromosome number from diploid to haploid Both the separation of sister chromatids and the reduction of chromosome number from diploid to haploid

Random alignment of homologous sister chromatids on the metaphase plate

Chromosomes are replicated during the ______ phase. G1 G2 S M meta-

S

The process that produces mRNA from DNA is called transcription. translation. replication. processing. post-translational modification.

transcription.

Consider a diploid organism whose karyotype shows it to have a total of 60 chromosomes. How many chromosomes would be contained in the sperm of this organism? 23 30 46 60 90

30

Question Correct Match Selected Match 1) 2 haploid daughter cells are produced at the end of this period of nuclear division. 2) DNA replication takes place before this(these) period(s) of nuclear division. 3) genetically identical daughter cells are created at the end of this period of nuclear division 4) homologous chromosome pairs line up at the metaphase plate 5) sister chromatids are pulled apart 6) chromosomes finish condensing All Answer Choices A. meiosis I B. meiosis II C. mitosis A and C B and C A, B and C

1) 2 haploid daughter cells are produced at the end of this period of nuclear division. A) meiosis 1 2) DNA replication takes place before this(these) period(s) of nuclear division. A and C 3) genetically identical daughter cells are created at the end of this period of nuclear division C) Mitosis 4) homologous chromosome pairs line up at the metaphase plate A) Meiosis 1 5) sister chromatids are pulled apart B and C 6) chromosomes finish condensing A, B and C

n garden peas, the allele for tall plants is dominant over the allele for short plants. A true-breeding tall plant is crossed with a short plant, and one of their offspring is test crossed. Out of 20 offspring resulting from the test cross, about _______ should be tall. 0 5 10 15 20

10

Decide which sequence of events is most CORRECT for the initiation and elongation steps of translation in prokaryotic cells? (1) initiator tRNA binds start codon on mRNA (2) small ribosomal subunit binds to mRNA (3) large ribosomal subunit binds (4) tRNA entry and peptidyl transfer reaction (5) translocation of ribosome and release of tRNA 1, 2, 3, 4, 5 1, 2, 3, 5, 4 1, 3, 2, 4, 5 2, 3, 1, 5, 4 2, 1, 3, 4, 5

2, 1, 3, 4, 5

Humans have __________ different types of autosomes. 46 44 23 22 11

22

Which of the following is true concerning a somatic cell mutation? A small fraction of the gametes carry the mutation. Half of the gametes carry the mutation. All of the gametes carry the mutation. Only a small group of cells within the organism is affected by the mutation. All cells within the organism are affected by the mutation.

Only a small group of cells within the organism is affected by the mutation.

Duplications and translocations differ in that translocations involve the loss of a chromosomal segment, whereas duplications involve addition of an entire chromosome. duplications involve the breakage and swapping of DNA segments on homologous chromosomes, whereas translocations are reciprocal exchanges on nonhomologous chromosomes. translocations involve the breakage and insertion of DNA segments in reverse order, whereas duplications are the breakage at different points on the chromosome. duplications lead to duplications of the chromosome, whereas translocations involve swapping of chromosome segments. translocations result in loss of chromosomal segments, whereas duplications result in significant additions to nonhomologous chromosomes.

duplications involve the breakage and swapping of DNA segments on homologous chromosomes, whereas translocations are reciprocal exchanges on nonhomologous chromosomes.

Color blindness is a recessive X-linked trait. A normal couple has a color-blind child. Who else in this family is probably color blind? the child's maternal grandfather the child's maternal grandmother the child's paternal grandfather the child's paternal grandmother the child's maternal grandmother or grandfather

the child's maternal grandfather